The present invention relates to a display apparatus and an image-pickup apparatus which enable a person to see different sides of a displayed object by viewing a displayed image while moving around it, and provide an image viewable as a three-dimensional image of the object.
A display apparatus has been proposed that displays three-dimensional images by using a rotary screen. In an example, this display apparatus produces a plurality of two-dimensional image data of a three-dimensional object as viewed from different directions around it, from three-dimensional image data representing the three-dimensional object (incidentally, in producing two-dimensional image data from three dimensional image data, a hidden-surface-erasure processing is applied in order to erase data for the unseen portions) and sequentially projects these two-dimensional image data on a rotating screen while sequentially changing the two-dimensional images projected on the screen according to the change of direction of the screen by rotation. According to this apparatus, when the screen is viewed from one position of the circumference, the image displayed on there changes gradually by rotating the screen quickly. Thus, by performing the image display, it is made visible the projected image of the screen as the three-dimensional image according to the visual afterimage effect. (e.g. refer to Japanese Patent Laid-open No. 2001-103515)
Additionally, in the case of the technology as described in Japanese Patent Laid-open No. 2001-103515, wherein three-dimensional image is obtained by projecting two dimensional images on a rotating screen, if the illumination distribution of the two-dimensional image to project is uniform, since illumination falls as it separates from an axis of rotation of the screen, an illumination distribution of the image projected on the screen becomes uneven. To prevent this problem, there is proposed e.g. in Japanese Patent Laid-open No. 2002-27504 a technology that makes the illumination distribution of two-dimensional image to project non-uniform, making the illumination distribution uniform for the images projected on the screen.
Another technology is presented in Japanese Patent Laid-open No. 2002-271820, wherein, an display apparatus has a configuration by which pictures of a display object are taken from different view points and slide images of such individual pictures are produced, and each time a rotating screen directs sequentially to those view points, the slide images obtained from the pictures taken at the corresponding view points are projected to the screen, and by increasing the rotational speed of the screen to 300-600 rpm, a pseudo three-dimensional image is formed on the screen by causing the naked eye afterimage. In another configuration, images of an object are serially taken by a camera moving circularly around the object, producing a cylindrical film of those images, and reading sequentially the images on the cylindrical film, then those images are imaged on a position of space through rotating mirror in synchronization with the reading of the cylindrical film, and by elevating the rotational speed high enough, a three-dimensional image floating in the space is obtained due to the naked eye afterimage.